Light Cahill Mayfly vs Blue-winged Olive Mayfly

Side-by-side species comparison

Attribute Light Cahill Mayfly Blue-winged Olive Mayfly
Scientific Name Heptagenia solitaria Serratella ignita
Order Ephemeroptera Ephemeroptera
Family Heptageniidae Ephemerellidae
Size 9-13 mm 7-10 mm body
Habitat Rivers & Streams Rivers & Streams
Diet Omnivores Omnivores
Regions North America Europe
Conservation Least Concern Least Concern

Light Cahill Mayfly

A pale-colored mayfly highly prized by fly fishers for imitating hatches. Nymphs prefer moderate current over gravel substrates.

💡

Did You Know?

The Light Cahill dry fly pattern, designed to mimic this species, has been used since the 1880s.

Blue-winged Olive Mayfly

A common mayfly of clean rivers and streams with distinctive blue-grey wings. One of the most important mayflies for fly fishing. Nymphs cling to stones in fast water.

💡

Did You Know?

So important to fly fishers that dozens of artificial fly patterns have been designed to imitate its various life stages.